Metal envelope for aircraft planes



pril 8, 1930. c. DORNIER METAL ENVELOPE FOR AIRCRAFT PLANES Filed Nov. 27. 1922 2 Sheets-Sheet 1- Unventor' Aprifi 8, 330.. c. DORNIER 7 METAL ENVELOPE FOR AIRCRAFT PLANES Filed Nov. 27, 1922 2 Sheets-Sheet,

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Patented Apr. 8, 1930 UNITED STATES PATENT OFFICE CLAUDIUS DORNIER, OF FRIEDRICHSHAFEN-ON-THE-BODENSEE, GERMANY, ASSIGNOR OF ONE-HALF TO THE FIRM: DORNIER METALLBAUTEN GESELLSGHAFT MIT IBE- SCHRIAN'K'JEEJR' HAFTUNG, ,OF FRIEDRICHSHAFEN, GERMANY METAL ENVELOPE non AIRCRAFT rLA vEs Application. filed. November 27, 1922, Serial No. 603,638, and in Germany December 12, 1921.

My invention has reference to the supporting planes of aircraft, and it particularly 'refers to all metal planes, one of its objects being to provide novel means for connecting the several strips or webs of sheet metal to each other and to the supporting beams, in pursuance whereof a great stability and resistibility is imparted to the planes, while the thickness of the supporting and fastening instrumentalities may be greatlyreduced.

The edge portions of the several sheets which are shaped in aocordancewith the configuration of the planes or wings, are turned upwards or downwards in a manner already suggested heretofore, so as to impart a kind of expanded U-sectional or channel shape to said sheet, provision ,being made to connect the bent edges of said sheets by embracing them with substantially channeled sheet metal members which are connected to said rims by rivets, bolts or the like.

The fins or ribs produced in this manner have heretoforebeen ordinarily arranged to extend in the direction of flight, and in such a manner that on one surface they were directed outwardly, and on the other surface inwardly, or they were arranged to protrude outwards on both surfaces. in this arrangement and construction of the projecting ribs .or fins produced in this manner, there was the dificulty of securing the envelope to the front beam, the so-called nose of the supporting plane, the said front beam as well as the other beams in view of the low resistive qualities of such envelopes opposed to the-forces acting upon the plane in the longitudinal di- 1 rection of the beams necessitating a very in such a manner that the ribs or fins produced at the joints of the sheets extend transversely to the direction of flight, that is to say, in parallel to the front and rear edges of the supporting plane. In this case the con mention of the joints at the front beam or nose of the supporting plane can be effected in the same manner, as with the other metal sheets, by bending the marginal portions outwards and connecting them to the beam by rivets, screws or the like. In the case of metal sheets of very thin material the fin or fins produced by the supporting beam and the turning over of the edges of the metal sheets, as well as the fins or ribs formed on the top' and bottom may be bridged over by suitably formed and figured metal sheets, so as to allow of using a comparatively small number of strong rivets in place of a large number of Weak rivets.

In view of the large resistance presented to forcesactingupon it by a longitudinally finned supporting plane of the kind referred to, the supporting beams employed may be comparatively thin and of light material, and they may be replaced by a succession of struts of light weight or by strips of sheet metal which are inserted between the turned-over edges of the sheets of metal and are riveted pressure side of the wings only where the velocity of the air is known to be comparatively small, and is even reduced to zero at certain points or with some shapes even takes the direction opposite to the flight, while on the other side of the supporting surface the edges of the metal sheets are turned inwards, and

are secured by rivets to the combination of struts or to the sheet metal strips. Also in such cases there is the possibility of readily assembling and repairing the plane by first constructing the inner joints, and by subsequently closing the supporting plane by the metal sheets with outwardly positioned In a preferred construction according to n while with the outwardly positioned ribs the flanges of the longitudinal beams are embraced by the U-shaped figured metal sheets. Every single metal sheet mayconsist of several separate strips which are connected to the figured sheets of metal running transversely thereof in the same manner as the individual sheets of metal by the turning over of the edges and by securing them to the transverse sheets by rivets or screws. In the case of injury to any of these strips the particular strip may be easily removed and exchanged in the same manner as the entire sheet by loosening the rivets or screws. If mere struts are used for stiffening purposes they are secured to the joints of the sheets so as to serve the purpose of flanges. The combination of struts in such cases may extend in the plane of the joints of the sheets and as a frame work between two adjoining sheet joints. Instead of struts recessed sheet metal webs may obviously also be used.

The invention will be more fully described with reference to the accompanylng drawing showing by way of example several forms of embodiment of the principles of my invention. In the drawing- Figures 1, 3 and 5 are diagrams of cross sections;

Figures 2 and 4 are diagrammatic representations of sections on lines A-A and BB respectively of Figures 1 and 3.

In the form of construction shown by way of example in Figures 1 and 2 the covering envelope consists of webs of sheet metal a running in parallel to the front and rear edges of the supporting plane,'the edges of the sheet metal webs bein turned up outwardly and their interme iate portion corresponding to the distance of the series of struts b which form the panel work of the longitudinal beams. The upturned edges of the webs of sheet metal are embraced by channeled strips of sheet metal 0, and the struts b are introduced between these upturned edges of the webs a, so that these edges constitute the booms for the series of struts. The edges are connected by rivets or the like with the strips 0 placed thereon and the struts. In the modifications shown as an example 111 Figures 3 and 4 the rib occurring at the front edge of the supporting plane as shown in Figures 1 and 2, is dispensed with in view of the fact that the sheet metal web a constituting the front or nose portion of the sup- ,porting plane possesses the necessary width and thickness to present suflicient resistance to strains acting thereon. Also the ribs upon the upper side of the supporting surface of the plane have been done away with by turning the edges of the sheet metal webs inwards, so as to produce a plane outer surface. These edges are secured by rivets to the recessed or perforated sheet metal strips d serving as longitudinal supporting beams. On

the bottom side, however, the edges are turned outwards, and are united, in the manner shown in Figures 1 and 3, to each other and to the sheet metal strips d by disposing thereon correspondingly formed metal sheets 0 and securing them by rivets or screws.

Instead of sheet metal strips 03 I may obviously also use series of struts or the like as shown in Figures 1 and 3, and in place of the series of struts c of Figures 1 and 3 sheet metal strips d may be used.

In the modification disclosed in Figure 5 each single sheet metal section situated between the longitudinal supporting beams is composed of several strips in a manner similar to the connection of the several webs to each other, the terminal strips of such composite sections constituting at the same time the top and bottom booms of the pairs of longitudinal supporting beams, so as to transform them into box girders. In case the sheet metal strips are formed of very thin walled material light transverse supporting beams acting as wing ribs and serving as supports for the composite sheet metal sections may be employed for the maintaining of the shape. This kind of composite outer envelope may also be arranged in such a manner that the ribs upon one side of the supporting plane are disposed at the inside similar to the construction shown in Figure 8 of the drawing.

In order to show the joints of the metal sheets with greater clearness they are shown on the drawing on a greatly enlarged scale as compared with the dimensions of the supporting plane.

I wish it to be understood that my inventlon is not restricted to the particular embodiments herein shown and described by way of example, nor to the particular mode of utilization enumerated, the scope of my invention admitting of various alterations and embodiments to adapt the invention to different conditions of application; and the language of this specification and claims is not intended as a limitation to the scope of my invention.

I claim I a 1. A wing construction for airplanes comprising'an envelope composed of a plurality of solid sheet metal strips having stiffening means extending outwardly of the surface and longitudinally of the wing, said means constituting air resistance elements acting to increase the carrying capacity of the airplane when in flight.

2. A wing construction for airplanes comprising an envelope composed of a plurality of solid sheet metal strips, and stiffening ribs extending outwardly of the surface of the envelop and longitudinally thereof to resist transverse breaking stresses, said ribs being formed to offer slight air resistance during flight whereby the carrying capacity of the airplane when in flight is increased.

3. A wing construction for airplanes comprising an envelope composed of a plurality" of metal sheets running transvesely to the line of flightand having outwardly turned flanges along their meeting edges forming stiflening ribs and means for connecting the sheets together, and channel means engaging about said flanges and constituting longitudinal beams for further resisting the transverse breaking stresses.

4. A wing construction for airplanes comprising an envelope composed of a plurality of metal sheets running transversely to the line of flight, stiflening ribs extending outwardlv on one of the surfaces of the envelope and inwardly on the other, and means for connecting the sheets together. 1

5. A wing construction for airplanes comprising an envelope composed of a plurality of metal sheets running transversely to the line of flight and having outwardly turned flanges along their meeting edges forming stiffening-ribs and means for connecting the sheets together, bracing means extending 5 within such envelope and between the meeting flanges of pairs of adjoining sheets, and means for connecting said flanges and bracing means together.

In testimony whereof I aflix my si nature.

so OLAUDIUS DOB IER. 

